In my classes I find that a lot of people who are new to sewing lose sight of how wide their seam allowance ought to be. And even those with a bit more experience sometimes need a bit of guidance on how to keep parallel lines of topstitching (like on bag straps) nice and straight. Here's a simple trick to help out in either case.
Ahhhh, the old Post-It Note trick.... Well, you can use masking tape instead - but Post-It Notes stay straight when you stick them down, are a doddle to move around and don't leave sticky residue. A small Post-It Note pad also fits more neatly into a sewing kit than a roll of masking tape.
1. Mark the depth of your seam allowance (or row of topstitching) from the edge of your fabric, and line that mark up with your needle. I usually snip a small nick in the fabric to mark the seam allowance, but a chalk pencil mark (shows up nicely in photographs and) is an absolutely fine alternative if you prefer not to snip.
2. Lower the presser foot on the machine and stick the Post It note down on the machine bed against the edge of the fabric. This will remind you which seam guide to use... in fact it will BE your new seam guide. (While you're sewing, keep the edge of the fabric running along the edge of the Post-It Note). Your seam allowance will be SUPER STRAIGHT (and your machine will probably be sewing better than this machine was... insert long story here and move on, folks).
3. If you're sewing parallel lines, you can repeat the process again to sew the next row....
4. ...and the next row. You can keep moving that note out again and again until it... well, loses it's sticky. You then have the NEXT leaf in the notepad to use. Luckily there are lots of them.
Copyright Nicole Mallalieu 2008